Electric heater



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J. H. ROSS.'

ELECTRIC HEATER.

FILED AUG-5. 1921.

Fe b. 27, 1923.

Patented Feb. 27, 1923.

PATENT OFFICE.

JOHN HENRY ROSS, OF TORONTO, ONTARIO, CANADA.

ELECTRIC HEATER.

Application filed August 5, 1921.

To all iii/1,0m. it may concern Be it known that I, JOHN HENRY Ross, 01'; (551 Yonge Street, in the city ot Toronto, in the county ot York and Province of Ontario, Dominion of Canada, have invented certain new and useful Improvements in Electric Heaters, o't which the following is a. speciication.`

My invention relates to an electric heater of' the type used in air drying machines and similar devices where a continuous current blown or drawn through the heater at al velocity which permits ot only that part of the current being heated which has direct contact with the resistance wire; the object ot the invention being to so devise the heater that the whole ol the i'uoving air must at some stage ot its progress, come into direct contact with the resistance wire and be in sta-ntaneously and uniformly heated to the desired degree, regardless of its volume or velocity.

In carrying out my invention I use a specially constructed core which enables the resistance wire to lie diagonally to and across the axis of' the moving current.

In the preferred construction, the core of the heater consists of' a set of longitudinally arranged and radially spaced .insulators tapered lengthwise ot the heater and rigidly held in hxed position by a correspondingr set ol.t insulator' holding members or arms and the resistance wire .is spirally wound on the insulators to lie diagonally to the axis of the heater and present a` heating surface across the path of the currentinto direct contactwithwhich the air must come as it flows through the heater.

In heaters where two or more degrees are required, the core may consist of a plurality ot similar tapered sections or units with the resistance wire of each section or unit concentric with the longitudinal axis of the heater and diagonal to the path of the air current passing through it.

To confine the air current in contact with thc resistance wire an insulated. casing is employed to enclose the heater, the internal diameter ot the casing being but slightly greater than the maximum diameter ot the tapered core.

ln the drawings;

Fig. l, an elevation ot the heater.

Fig. Q. is acentral vertical section of Fig. l, taken on the line .fu-sr, and

Serial No. 489,989,

Fig. 3, is a horizontal section ot Fig. l taken on the line j//-g/.

Referring to the drawings, it will be seen that the skeleton holding frame is arranged as follows z--l is the upper end plate or disk having a central insulating Zone 2 through which the feed wires 3, 4, and 5 pass.

6 is the lower end plate or disk and between this and the upper disk l are rigidly attached the longitudinal insulator holding men'lbers or arms 7. These arms 'T arc radially arranged upon their supporting end plates or disks l and (i, and are stepped or serrated lengthwise at intervals to provide a plurality ot tapering sections S. These longitudinal holding members or arms 7 are ot U-shape cross-section and embrace and rigidly hold the insulator strips 9. The strips 9 are of corresponding shape and taper in a similar manner to the holding members or arms 7 and their edges are provided with a series oit spaced notches 10, for the reception and retention of the resistance wire l1.

The serrated formation ot the insulator strips 9 provides a plurality of similar tapered sections' or units 9 with the spirals or coils of the resistance wire of each section or unit concentric with the longitudinal axis ot the core and the perimeters ot' the spirals or coils in a plane tangential thereto and diagonal to the path of the air current passing through the heater, thereby presenting a heating surface transversely across the entire path of the current and instantaneously and uniformly heating the whole of the Inovingrv air by direct Contact with it.

The resistance wire 11 is wound spirally around the serrated insulator strips 9 and retained in position by the spaced notches l0, being connected to thc feed wires and 4. An `iiitermediate connection with the resistance wire lil is made with the feed wire 5 which is )neteral'ily connected. as shown, at ay point equidistant from the connections with the lfeed wires 3 and 4. At spaced intermediate points in the central bore of the skeleton 'frame are immovably fixed spacing disks 13. The construction hereinbefore described is enclosed within the casing 12, the internal diameter ot which is but slightly greater than the maximum. diameter of the core to confine the air in close Contact with the resistance wire as it flows through the heater, the air passing over the first heating cone .is heated, and is repeatedly reheated on comingin Contact with each successive resistor cone, finally reaching a desired prede` termined temperature, this arrangement eit'ecting a. direct Contact with the air with the resista nee Wire and enabling every thermal unit to be etl'eftive in raising the temperature, ol'V the contacting air.

lilaving now particularly described and as certained the nat-ure oi my said invention and in what manner the same is to lie perl'formeth l declare that what l claim l. In an electric heater element au insulated core comprising an insulator consisting;r of a plurali@7 of taliiering insulator sections, electric resistors disposed upon said sections, to heat and repeatedl)1 reheat a current ot air contacting with said resistors.

2. In an electr-ie heater element, an insulated core comprisinga set of spaced insulators each oit which is stepped lengthwise at intervals to provide a plurality of tapering insulator sections, electric resistors dis posed upon. said sections, to heat and repeatedly reheat a current ot' air contacting With said resistors.

3. In an electric heater element, an insulated core conilnisingDT a set ot supporting end plates, a set ot' arms radially arranged on said end plates and each stepped lengthwise at inter.'als for toriniifi plurality oit tapering sections, and a set ot insulators held by said arms and each of which is stepped length- Wise al; intervals 'tor forming a` plurality ot tapering: insulator sections, elect-ric resistors disp sed upon said sections, to heat and repeatedly reheat a current of air Contacting with said resistors.

Dated at the city oi Toronto, this 16th da),7 ot July, A. D. 1921.

JOHN HENRY ROSS. lVitnesses H'rANLm Bienes, lll. T. MILLER. 

